Add a README.
Initial publication of S2 geometry library for Go.
Resolve naming conflicts in tests.

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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=43923623
Make the s2.CellID.Children method public.
Application: Generating four neighboring cells of a given cell.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=47567505
Add s2.CellID.EdgeNeighbors.
Port of S2CellId::GetEdgeNeighbors.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=48012182
Fix comment on range of normalized angles.
Add Euclidean distance between r3 vectors.
Implement AddPoint on s2.Rect, s1.Interval and r1.Interval.
Fix cellIDFromFaceIJ in 32-bit builds.
Add gitignore
Add LICENSE